What is the congruent sign?

The congruent sign is a symbol used in geometry to indicate that two figures have the same size and shape. The sign consists of two parallel, horizontal lines topped by a single slightly wavy line. This is a combination of the "equal" sign and the "similar" sign.

Line segments that are the same length are identified as congruent. Polygons are considered congruent if they have exactly the same size and shape. For instance, two identical octagons are congruent. In addition, if the polygons were to be placed one on top of the other, the sides of each polygon that matched would be identified as "corresponding." Corresponding angles of congruent polygons also match.